System and method for producing concentrated food products with fractionation concentration

ABSTRACT

An improved processing method and system for producing tomato paste and other food products affected by viscosity. Tomatoes are processed into tomato juice. The juice is provided to a decanter that separates or fractionates the juice into two portions—a thicker, more viscous cake portion and a thinner, less viscous serum portion. The serum portion is concentrated by removing a portion of water using an evaporator such as a thin film or juice evaporator. The cake portion can be concentrated if necessary with a drier. The serum and cake portions are recombined to produce a tomato paste having improved color, texture, flavor and nutrition.

FIELD OF THE INVENTION

[0001] This invention relates to food products and a system and methodfor producing food products. In particular, the present inventionrelates to tomato paste and similar food items that are produced byseparating tomatoes or food items into portions or fractions havingdifferent viscosity, concentrating one or more of the portions, andre-combining the portions to form a food product such as tomato paste.

DESCRIPTION OF RELATED ART

[0002] Tomatoes or derivative tomato products such as juice, puree andpaste can be added as food ingredients to a food product to provide, forexample, flavor, color, texture and viscosity. Tomato paste is onecommon product produced from tomatoes. To produce tomato paste, water istypically removed from tomatoes or tomato juice via dehydration orevaporation.

[0003] Using tomato paste can be advantageous, compared to freshtomatoes or tomato juice, for a number of reasons. For example tomatopaste may provide improved taste, appearance, and be advantageous forthe following economic considerations:

[0004] a. Storage capabilities—aseptically bulk packaged tomato pastecan be stored for extended periods of time (e.g., up to several years)prior to consumption. These storage capabilities provide flexibility inshipping, transportation, and sales.

[0005] b. Reduced shipping costs—bulk tomato paste typically weighs lessthan raw tomatoes as a result of lower water content. Thus, shippingcosts are reduced.

[0006] c. Supply flexibility—a year round supply of tomato paste can bemaintained in spite of the season for harvesting fresh tomatoes beingapproximately 100 days.

[0007] d. Cooking requirements—some products require tomato paste ratherthan fresh tomatoes or tomato juice based on a recipe's water contentlimitations.

[0008] Known system typically process tomatoes by directly processingthe entire or unfractionated tomato stream. For example, tomatoes arechopped into a liquid or liquid-like product and supplied to anevaporator. The unfractionated tomato stream becomes increasinglyconcentrated as the evaporator heats the tomato stream and removes waterfrom the stream.

[0009] Such conventional systems, however, typically have a number ofshortcomings. First, as the paste product becomes more viscous (thickeror more resistant to flow), the tomato paste becomes increasingly moredifficult to manipulate. The increasing viscosity is the result ofvacuum, heat, shear and recirculation of the thickening paste. Portionsof the paste can be “burned” onto evaporator surfaces as the surfacesare heated and the viscous paste can stick to the surfaces.Consequently, the resulting tomato paste can be burned or overheated,resulting in diminished tomato paste quality, e.g., reduced color,flavor and nutrients.

[0010] Moreover, additional cleaning and maintenance of evaporatorequipment may be necessary as a result of the “burning” effect.Maintenance and cleaning requires additional time and resources which,in turn, lead to inefficient processing and reduced productioncapabilities.

[0011] Additionally, in order to process the increasingly viscous paste,known systems typically use more powerful evaporators that can handlehigher viscosity paste. These types of evaporators may usere-circulation turbine pumps to pump and re-circulate the increasinglyviscous tomato paste. These more powerful, larger evaporators usuallyare more expensive. Further, larger evaporators typically consume morepower and are more expensive to operate. Additionally, processingunfractionated streams of tomato juice typically takes a significantamount of time (e.g., two to three hours for a reasonable sized batch).Consequently, systems that produce tomato paste by directly processingunfractionated streams of juice often are not time, cost, and energyefficient and can produce lower quality tomato paste.

[0012] Other known systems separate portions of tomato paste to formderivative products. For example, a portion can be removed from a tomatojuice stream, and the evaporator can concentrate the remaining portion.Typically, however, these known systems also have a number ofshortcomings. First, these systems produce separated components that areuseful only in limited circumstances based on the quality and nature ofthe components. For example, the thicker component is typically a dense,powder-like substance that can be milled and used as a flavoring. Thethicker component, however, is often not suitable for tomato paste.Further, the remaining portion is often too thin to be used as tomatopaste. Thus, these known systems separate components of a tomato stream,but may not be able to produce tomato paste in an effective matter.Further, the dense powder and liquid components typically cannot becombined due to their different compositions. If the portions arecombined, a low quality, chalky tomato paste-like product may beproduced having diminished color, texture, and taste. Thus, knownsystems that separate tomato components are often not as effective asdesired to produce quality tomato paste in an efficient manner.

[0013] There is a need, therefore, for a system and a method forproducing tomato paste and other similar products with improvedviscosity, color, nutrients and flavor in a more cost, energy and timeefficient manner.

SUMMARY OF THE INVENTION

[0014] The present invention provides-an improved system and method forprocessing tomato products to produce a paste with enhanced taste andcolor in a more efficient manner.

[0015] One embodiment of the present invention provides a system andmethod that processes tomatoes into a stream of tomato “juice.” Thejuice stream is separated-or fractionated into two portions—a serumportion and a cake portion. The serum portion has a lower viscosity thanthe cake portion. In other words, the cake portion is thicker and moreresistant to flow relative to the serum portion. After these portionsare separated, the serum portion is concentrated using, for example, anevaporator. The cake portion can also be concentrated, if desired, usinga drier mechanism or other suitable evaporator. The cake portion and theconcentrated serum portion are re-combined to form an improved tomatopaste. Alternatively, the portions can be separately processed and/orpackaged as separate products or ingredients.

[0016] The cake portion includes a majority of insoluble solids relativeto the serum portion. As a result, the serum portion can be concentratedmore easily with an evaporator for enhanced appearance and taste.Further, less evaporation time and energy are required to process theserum portion, thereby reducing capital and energy costs associated withthe evaporator. Thus, less expensive and robust evaporators can be used.A drying mechanism can be used to concentrate the cake instead of anevaporator. As a result, the present invention can reduce or eliminatedegradation of tomato juice stream resulting from “burn on” of cakecomponents onto evaporator surfaces. Further, cleaning and maintenancecosts can be reduced while producing a tomato paste product withenhanced flavor, texture, color and nutrition.

[0017] Also in accordance with the present invention, a decanter can beused to separate tomato juice into cake and serum portions. The decantercan separate the portions using different techniques. One exemplarydecanter is configured as a centrifuge with an inner weir. As thecentrifuge rotates, the cake gravitates to the inner surface of thedecanter and is separated from the serum with the weir. The fractionatedcake portion can advantageously have the following characteristics:about 5%-35% ofthe tomato stream byweight, about 5%-60% insoluble solidsby weight, about 3%-16% soluble solids by weight and a concentration ofabout 3-13 brix. The fractionated serum portion can have the followingcharacteristics: about 65%-95% ofthe tomato streambyweight, about0(trace)-10% insoluble solids byweight, about 3%-17% ofsoluble solids byweight and a concentration of about 3-16 brix.

[0018] In further accordance with the invention, if the cake and serumstreams are re-combined, the concentration of the re-combined stream canhave a concentration of about 15-40 brix. If the cake and serum portionsare not re-combined, the cake portion can have a concentration of about5-99% of solids. For example, a thick cake can be formed if the cakeportion is about 5% solids, whereas a powder that can be milled can beformed if the cake portion is about 99% solids. The serum portion can beconcentrated to a concentration of about 22-75 brix.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Referring now to the drawings in which like reference numbersrepresent corresponding parts throughout:

[0020]FIG. 1 is a general block system diagram of portions used toprocess a stream of tomato juice by fractionating the juice into cakeand serum portions, and re-combining the portions to form a tomatopaste;

[0021]FIG. 2 is a general block system diagram of portions used toprocess tomato juice by fractionating the juice into cake and serumportions, and separately processing the portions;

[0022]FIG. 3 is a system diagram illustrating one example systemconfiguration and example operating parameters;

[0023]FIG. 4 is a diagram illustrating an example decanter configurationfor fractionating a tomato juice stream into cake and serum portions;

[0024] FIGS. 5A-B are flow diagrams illustrating a method of producingtomato paste by separating the tomato juice stream into cake and serumportions, and re-combining the portions to form tomato paste; and

[0025] FIGS. 6A-B are flow diagrams illustrating a method of separatingthe tomato juice stream into cake and serum portions, and separatelyprocessing the portions.

DETAILED DESCRIPTION

[0026] In the following description of embodiments of the invention,reference is made to the accompanying drawings which form a part hereof,and which is shown by way of illustration specific embodiments in whichthe invention may be practiced. It is to be understood that otherembodiments can be utilized as structural changes maybe made withoutdeparting from the scope of the present invention.

[0027] One aspect of the invention provides a processing system thatfractionates or separates tomato juice or a tomato stream or othersimilar substance into different portions, i.e., cake and serumportions, and later re-combines the portions. As generally illustratedin FIG. 1, the processing system transports a product 100, such astomatoes, on a conveyor or other transport system 105. Those persons ofordinary skill in the art will recognize that various tomato products100 can be processed, such as fresh tomatoes, tomato juice, tomatoslurry, a mixture of tomato juice and tomato pulp, or other tomatoderivatives. However, the invention is not so limited. Those persons ofordinary skill in the art will also recognize that other food productscan be processed. For example, the present invention can be used toprocess or produce other food items that are affected by viscosity suchas, for example, chili paste (which can be thicker than tomato paste),and other Suit or vegetables where limiting viscosities prevent orinhibit evaporation, such as peas for pea soup. A further exampleapplication of the present invention is to process apples or apple ciderto form a concentrated apple puree. The puree can be used to make applepies and other apple products. However, for purposes of explanation,this specification refers to processing raw tomatoes into a “juice” thatis fractionated into serum and cake portions that can be re-combined toform a tomato paste after one or more of the portions has beenconcentrated.

[0028] Tomatoes are transported along the conveyor and are chopped witha chopping mechanism 110. Chopped tomatoes are provided via a pump 115to an enzyme processor 120 for enzyme breaking or inactivation. Thechopping mechanism 110 can be one of many mechanisms that chops tomatoesinto tomato pieces including, but not limited to, a knife, a rotatingknife, rotating blades, a blender mechanism, and other cutting andchopping devices capable of cutting fruits and vegetables.Alternatively, the chopper 110 and pump 115 can be combined into asingle unit. For example, a device that combines both chopping andpumping functions is chopper pump model no. STH4R12S, available fromVaughn, Co., Inc., Montesano, Wash.

[0029] The enzyme processor 120 removes selected enzymes that affect theviscosity of chopped tomatoes. In other words, enzymes are inactivatedduring “hot breaking” or “enzyme breaking.” Example enzymes that can beremoved or inactivated include pectin galacturonase, pectin methylesterase and other enzymes in fresh tomatoes. One exemplary enzymeprocessing or “breaking device” 120 that can be used is model G ElDorado, available from Rossi & Catelli S. P. A., Parma, Italy. Thisexemplary enzyme breaking device can be set to operate at differentconfigurations and temperatures for hot or cold breaking, as laterdescribed.

[0030] If necessary, the chopped tomatoes can be processed with aninitial or preliminary evaporator 125. The initial evaporator 125removes a portion of the water from the chopped tomatoes to make thetomatoes more viscous or thicker. One exemplary evaporator 125 that canbe used for this purpose is a T.A.S.T.E. evaporator, available from FMCFood Tech, Inc., Citrus Systems Division, Lakeland, Fla. Anotherexemplary evaporator 125 that can be used is an EC series rising filmevaporator, available from Tetra-Pak, Inc., Vernon Hills, Ill.

[0031] Enzyme inactivated tomato pieces can be further processed andfiltered using a pulper or finisher 130. One exemplary pulper/finisher130 that can be used is a Butterfly TC6 depulper, available from Rossi &Cateri S. P. A., Parma, Italy. The pulper or finisher 130 removes solidsfrom the tomatoes such as outer skins and/or seeds to form a tomato“juice” or “juice stream” 132. More specifically, one type of thepulper/finisher 130 forces chopped tomatoes through a screen, filter, orfilter screen having holes or apertures of specific size. Example screensizes that can be used to remove seeds and/or peels to form the juicehave apertures with dimensions of approximately 0.027″ to 0.156″. Mosttomato seeds can be removed with screen having apertures of up to0.074″. As tomato pieces pass through the apertures, seeds and/or peelsare removed or filtered from the tomatoes to produce tomato juice 132.As a result, the juice 132 includes portions less than or equal to thesize of the finisher-pulper 130 screen. Different food products can beprocessed with different pulper-finisher apertures depending on thequantity and size of seeds and desired smoothness or coarseness offibers in the juice 132.

[0032] Those persons of ordinary skill in the art, however, willrecognize that one or more of the portions 110-130 may not be necessarydepending on the characteristics and type of tomato or food productprocessed. However, for purposes of explanation, this specificationrefers to the pulper/finisher 130 producing “tomato juice” 132, althoughjuice 132 may be formed at different stages.

[0033] The tomato juice 132 is supplied to a decanting centrifuge 135(hereafter referred to as decanter 135). The decanter 135 separates orfractionates juice 132 into a serum portion 140 and a cake portion 145.One exemplary decanter that can be utilized is a Tetra Aldex® decanter,model no. NX438, available from Tetra-Pak, Inc., Vernon Hills, Ill. Thisexample decanter uses a weir to separate the portions, as will be laterdescribed in further detail in connection with FIGS. 3 and 4. Anotherdecanter that can separate tomato juice or tomato puree 132 into cake140 and serum 145 portions is a clarifier decanter, model no. CA755-0012 or model no. CA 755-01-12, available from Westfalia Separator,Inc., Northvale, N.J.

[0034] Those persons of ordinary skill in the art will recognize thatvarious decanters and decanter configurations can be used. For example,instead of a centrifuge, the same fractionation technique can beachieved by using a press with one or more apertured filter screens(which can be used for processing apples or apple cider). A furtheralternative fractionation device can be a filtration membrane such as anultrafiltration membrane. However, for purposes of explanation, thisspecification refers to a decanting centrifuge for fractionating a juicestream 132 into serum 140 and cake 145 portions.

[0035] The serum portion 140 is concentrated using an evaporator 150.The output of the evaporator 130 is a concentrated serum 160. Evaporator150 can be the same as the initial evaporator 125 or similar. However,since the serum is thinner and less viscous than the cake portion or anunfractionated tomato stream, a smaller (and usually less expensive andmore energy efficient) evaporator 125 can advantageously be used toconcentrate the serum portion 140. One exemplary evaporator 125 that canconcentrate the serum portion 140 is a juice evaporator, ThermallyAccelerated Short Time Evaporator (T.A.S.T.E.) 6 effect 6 stageavailable from FMCFoodTech Food Processing Systems, Parma, Italy. As aresult of using a smaller evaporator, capital expenditures and energycosts for processing food products can be reduced. Further,concentration times can also be reduced since the serum is thinner thanan unfractionated stream and easier to process in a shorter period oftime. For example, some known systems may take an hour or more toprocess a batch of unfractionated tomatoes into a tomato paste. However,the thinner, fractionated serum can be processed in less time with asmaller evaporator (e.g., 5 minutes-1 hour).

[0036] The cake portion 145 can also be concentrated, if necessary with,e.g., a drier 155 to produce a dried cake portion 165. One exemplarydrier 155 that can be used is a Refractance WindowTM drier, availablefrom MCD Technologies, Inc., Tacoma, Wash. With this exemplary drier,the cake 145 can be sprayed across the belt with a sprayer (not shown)and passed through the drier to evaporate water from the cake, therebyforming a concentrated cake portion 165. Other evaporation systems canalso be used to concentrate the cake.

[0037] The concentrated serum portion 160 and the cake portion 145 (orconcentrated cake 165, if desired) are re-combined using a combiner orcombination unit 170 to form a re-combined stream 171 or tomato pasteproduct. One exemplary combination unit 170 that can be used is apositive displacement pump, model no.220, available from Waukesha CherryBurrell Products, Delvan, Wis. Alternatively, the combiner 170 can be anin-line static mixer, e.g., model no. SAN 42499, available from KomaxSystems, Inc., Wilmington, Calif. Indeed, various combiners 170 can beused. The re-combined or second juice stream 171 output by the combiner170 is sterilized with a sterilization unit 180, as necessary, andcooled with a cooling mechanism or cooler 185, as necessary. The tomatopaste can be packaged, shipped, stored for later consumption, or fartherprocessed as desired.

[0038] Referring now to FIG. 2, in an alternative embodiment, the serum140 and cake 145 portions are not re-combined. Instead, the serum andcake portions are processed individually. More specifically, the juicestream 132 is processed by the decanter 135 to produce the serum 140 andcake 145 portions as previously described. The serum portion 140 isconcentrated with an evaporator 150 to produce a concentrated serumportion 160. The cake portion 145 can be concentrated, if necessary,with a drier to produce a concentrated cake portion 165. However, thecake and serum portions are then separately processed, e.g., aresterilized with one or more sterilizers 180, cooled with one or morecoolers 185 and packaged with one or more packagers 190. Thus, in thisalternative embodiment, serum and cake portions are separately producedwhereas tomato paste is ultimately produced by re-combining the portionsas illustrated in FIG. 1. The resulting concentrated serum 160 can beused as a soup base or flavoring since it is thinner than the cake. Thecake portion 145 or concentrated cake portion 165 can be used as a coloringredient, a source of nutritional fiber for foods including a tomatoproduct, and a source of lycopene.

[0039] These and other aspects of the present invention are described infurther detail with reference to the system and decanter diagram of FIG.4, and flow diagrams of FIGS. 5A-B and 6A-B.

[0040]FIG. 3 illustrates one exemplary system configuration forprocessing tomatoes by re-combining the serum and cake portions to formthe tomato paste. Of course, those persons of ordinary skill in the artwill recognize that the following system parameters are merelyillustrative of many system parameters and are not so limited. Further,FIG. 3 illustrates the primary portions of the system. For example,depending on the state and type of tomatoes, chopping, pulping, andenzyme breaking may be performed. Additionally, one or more additionalpumps may be used to direct the juice, serum portion, cake portion, andtomato paste product to the next processing portion.

[0041] Initially, tomatoes 100, are provided to an evaporator 125, suchas a thin film evaporator, at a rate of about 112.4 tons per hour(tons/hr) at a concentration of about 5 brix. Different tomatoes withdifferent brix concentrations can be processed, but the concentration ofraw tomatoes can range from 3-7 brix. The concentration measurement“brix” refers to a percentage of sugar and other soluble solids presentin the tomatoes. Thus, for example, tomato pieces having 3-7% sugar orsoluble solids have a concentration of 3-7 brix. Tomato products havinghigher brix concentrations are generally sweeter and more flavorful as aresult of higher sugar content.

[0042] The evaporator removes moisture from the tomatoes at a rate ofabout 50.0 tons/hr and outputs the tomatoes at about 62.4 tons/hr with aconcentration of about 9 brix. The tomatoes can be processed by a pulper130 resulting in a juice stream 132. The juice stream 132 is thenprocessed by the decanter 135 at about 242 gallons per minute(gal/minute). The decanter fractionates the juice into serum and cakeportions 140, 145 that are pumped through respective pumps 300, 305. Theserum is pumped to an evaporator 150, such as a thin film/juiceevaporator, at a rate of about 53.1 tons/hr at a concentration of about9.0 brix. The cake 145 is pumped to a drier 155 at a rate of about 9.4tons/hr at a concentration of about 9.0 brix. As previously mentioned,evaporator 150 can be a less robust (and less expensive) evaporator,such as a thin film juice evaporator, since it is processing the “thin”serum portion 140 of the juice stream 132. The evaporator 150 removesmoisture from the serum 140 at rates of about 13.8 tons/hr and 25.6tons/hr, thereby concentrating the serum. The concentrated serum 160exits the evaporator 150 at a rate of about 13.6 tons/hr at an increasedconcentration of about 35.0 brix. If needed, the concentrated serum 160can be further concentrated with additional evaporators 310 and 315.However, this example configuration does not utilize these additionalevaporators as shown by consistent flow rates into the combiner 170, butare illustrated to show additional optional concentrating.

[0043] The drier 155 removes moisture from the cake 145 at a rate ofabout 1.8 tons/hr, resulting in concentrated cake 165 exiting the drier155 at a rate of about 7.6 tons/hr with a concentration of about 11.2brix. Those persons of ordinary skill in the art will recognize that thedrier 155 is optional. The concentrated serum 160 and the cake 145 orconcentrated cake 165 are re-combined using combiner 170, such as astatic mixer. The re-combined stream 171 includes about 64% serum byweight and about 36% cake by weight. The resulting stream 171 or tomatopaste product exits the combiner 170 at arate of 23.0 tons/hour with aconcentration of 26.5 brix. Those persons of ordinary skill in the artwill recognize that many variations on the previously describedoperating parameters can be used.

[0044] Turning to FIG. 4, one exemplary decanter 135 includes acentrifuge body 400 supported by base 405. The centrifuge body 400rotates around a bearing 410. The decanter includes an input 420, weir430, serum output 440, cake output 450 and a scraping mechanism such asrotating auger 460.

[0045] Juice 132 is provided to the decanter 135 through the input 420.As the decanter rotates, the thicker cake portion is separated from theserum section. The cake portion gravitates to the inner surfaces 402 ofthe centrifuge body 400. The less dense serum portions remain in thegeneral middle area of the decanter, i.e., the thinner serum does nottend to migrate to the inner surfaces of the centrifuge body. The cakeportions 145 collecting around the inner surfaces 402 of the centrifugebody 400 are illustrated as dashed lines 145a in the top and bottomsections of the decanter cross section.

[0046] The weir 430 can be an interior wall or ring with an inneraperture 431. The weir serves as a wall to hold the cake and block itfrom exiting through the serum outlet 440. Thus, the weir separates thecake and serum portions and permits the less dense, thinner serum 140,to pass through the decanter through the serum outlet 440. The weirheight is selected such that the cake portion is retained against theinner surface of the centrifuge body, thereby separating the cake fromthe serum. The cake can be removed from the decanter via cake output 450near the bottom of the body. More specifically, the cake can be“scraped” off the inner surface of the rotating centrifuge bowls by, forexample, a rotating scraper or auger 460 (partially illustrated in FIG.4). The auger surfaces rotate along the inner surface of the centrifugebody, thereby removing the cake 145a from the inner surface. The cake isthen directed to the cake outlet or discharge port 450. The scraper canbe configured to closely scrape the wall or be positioned further awayfrom the inner surface such that the scraper removes a smaller quantityof cake from the inner surface of the centrifuge body. Cake and serumseparation can be adjusted by adjusting the rotation speed of thedecanter, rotating speed of the internal cake scraping auger (scrollspeed differential), product temperature and the height of the weir.

[0047] One example decanter or centrifuge 135 that can be used is aTetra Pak Inc., NX438 centrifuge operating at approximately 3400revolutions per minute (rpm), having a 132 millimeter (mm) pond depthweir plate and a scroll speed differential of 20-40 rpm. The separationefficiency of the decanter is improved as the temperature increases. Atemperature of approximately 180 to 190 degrees Fahrenheit typicallyresults in separation of the cake and serum portions at the examplespeed.

[0048] Those persons of ordinary skill in the art will recognize thatother scraping mechanisms can be utilized for removing cake from aninner surface of the centrifuge body. For example, instead of a rotatingauger, the scraper can be a member that is displaceable along one ormore of the inner top, bottom or side surfaces of the centrifuge body.Thus, the displaceable member can move from one end of the decanter tothe other end to remove cake from the interior decanter surfaces.

[0049] Having described the general system portions and decanterconfigurations, FIGS. 5A-B and 6A-B illustrate the method for processingtomatoes with the system. Referring to FIG. 5A, step 500, tomatoes arereceived and initially processed (e.g., cleaned, sorted, etc.). Forexample, a fruit dump with water flumes and a conveying elevator withwater or cleaning sprays can be used. The tomatoes are transported tothe chopping mechanism and, in step 505, are chopped into tomato pieces.Chopped tomatoes have a natural brix concentration of about 3-7 brix. Ofcourse, different tomatoes and different food products can havedifferent brix concentrations.

[0050] In step 510, enzymes are removed from or inactivated in thechopped tomato pieces. This process is referred to as “enzymeinactivation” or “enzyme breaking” or “hot breaking”. More specifically,enzymes that are involved in the reduction of viscosity can be removedfrom or inactivated in tomato pieces, e.g., pectin galacturonase, pectinmethyl esterase and other enzymes present in tomatoes that causeviscosity reduction.

[0051] Enzyme breaking can occur at “cold” or “hot” temperatures. Incold enzyme breaking, chopped tomatoes are subjected to approximately150 to 170 degrees Fahrenheit for a period of about 1 to 10 minutes. Inhot enzyme breaking, chopped tomatoes are subjected to approximately 200to 230 degrees Fahrenheit for a period of about 15 seconds to 10minutes. Whether hot or cold enzyme breaking is used can depend on thedesired viscosity effect. For example, tomato paste made from “hotbroken” tomatoes typically has higher viscosity than “cold broken”tomatoes. However, tomato paste produced with hot broken tomatoestypically has less vibrant color than tomato paste produced with coldbroken tomatoes. Breaking parameters can be adjusted depending onoperating parameters and the desired enzyme breaking effect.

[0052] Continuing with block 515, chopped and enzyme inactivatedtomatoes are processed with a pulper or finisher, if necessary. Thepulper/finisher removes solids such as skins, seeds and/or other fibrousmaterial from the tomatoes. The pulp and fibers remaining within thefinished tomatoes or “juice” are reduced to a specific size.Pulping-finishing generally occurs at a temperature of approximately 190to 210 degrees Fahrenheit if the tomato pieces are subjected to hotbreaking. If the tomato pieces are subjected to cold breaking, thepulping-finishing process can occur at approximately 150 to 170 degreesFahrenheit.

[0053] Pulping and finishing tomato pieces results in a tomato “juice”or pulp product (“tomato juice”). However, those persons of ordinaryskill in the art will recognize that “juice” can be formed by techniquesbesides pulping and finishing, e.g., by repeated chopping, crushing, orother actions to form juice. Thus, the tomato juice is not necessarily aproduct of a pulping/finishing step.

[0054] The tomato juice can be initially concentrated, if necessary, byremoving water with an evaporator in step 520. The degree of evaporationcan depend on the initial liquid content of the tomato juice. Forexample, hot tomato juice or juice processed with hot breaking can beexposed to a vacuum (e.g., 10-30°Hg) to remove a percentage of waterfrom the juice. Thus, the more water that is removed from the juice, themore viscous or resistant to flow the juice becomes.

[0055] Continuing with step 525, tomato juice is separated orfractionated into serum and cake portions with a decanter. One exampledecanter configuration for separating the portions is a weir and scraperor auger configuration. The cake portion is more viscous and containshigher percentages of insoluble solids and pectins of the tomato. Thecake portion can comprise about 5% to 35% of the total tomato juicestream. Further, the cake portion typically includes a large percentageor majority of lycopene and other “color” compounds. The cake portionincludes about 5%-60% insoluble solids by weight and about 3-16% solublesolids by weight. The cake portion can have a concentration of about 3to 13 brix.

[0056] The serum portion of the tomato juice stream is less viscous thanthe cake that includes lower percentages of insoluble solids and pectinof the tomato compared to the cake portion. The serum portion cancomprise approximately 65% to 95% of the total tomato juice stream byweight. The serum portion includes about 0(trace) amount to about 10%insoluble solids by weight and about 3%-17% soluble solids by weight.Further, the serum portion can have a concentration of about 3-16 brix.

[0057] In step 530, the serum portion 435 is concentrated. Morespecifically, the thin, less viscous serum fraction can be concentratedby removing water with, for example, a smaller, less robust (and lessexpensive) evaporator compared to evaporators used in known systemswhich process unfractionated tomato juice. Examples of evaporators thatcan be used to concentrate the serum portion in step 445 include, butare not limited to, a rising film evaporator, a falling film evaporator,a thin film evaporator, and other concentrating units such as a reverseosmosis concentrator or a direct osmosis concentrator. The serum portioncan be evaporated more easily than unfractionated juice because thethinner serum can be re-circulated in the evaporator more often and moreeasily, resulting in improved heat transfer. Additionally, maintenanceand cleaning and related costs can be reduced. As a result of lowerlevels of insoluble portions in the concentrated juice, less or no cakeis burned onto evaporator surfaces. Utilizing smaller and less robustevaporators is also beneficial because of lower capital and operatingcosts. Smaller evaporators can also operate under reduced heat ortemperatures, vacuum requirements, re-circulation requirements, andresidence time to evaporate a given amount of water from the serum.

[0058] If necessary, in step 535, the cake portion can be concentrated.The thicker, more viscous cake portion contains higher percentages ofinsoluble solids and is also subjected to reduced heat, vacuum,re-circulation shear, and residence time. For example, instead ofprocessing the thicker cake portion in the unfractionated stream with anevaporator, the cake can be concentrated using a drying mechanism suchas a model no. 1 or a model no. 5 drier available from MCD Technologies,Inc., Tacoma, Wash. As a result, less cake “burn” occurs since ahigher-powered evaporator is no longer necessary to concentrate thejuice stream.

[0059] The fractionated cake and concentrated serum portions arere-combined in step 540 with a combination unit, e.g., a positivedisplacement pump or an in-line static mixer as previously described.Re-combining the cake and serum portions results in the formation of a“re-combined” or “second” tomato stream 545. The brix concentration ofthe second stream 545 is about 15 to 40 brix. During re-combination, allor a portion of the cake portion can be added to the concentrated serum.For example, 50%-100% of the cake can be re-combined with theconcentrated serum. Indeed, other cake percentages can be used dependingon particular needs and desired viscosity (viscosity increases aspercentage of cake increases). Increasing cake quantities lowers thebrix of the re-combined stream since the cake brix is approximately 3 to20 brix, preferably 3-13 brix, while the serum brix is about 22-70 brix.As a result, the concentration of the re-combined stream 545 can beabout 15 to 40 brix, preferably about 22-40 brix.

[0060] Continuing with FIG. 5B, the second or re-combined stream 545 canbe further concentrated in step 550, if necessary, and sterilized asnecessary in step 555. The re-combined stream is cooled if necessary instep 560. For example, the stream can be transferred to a flash cooler.Alternatively, a heat exchanger or other process may be used to cool thepaste. Those persons of ordinary skill in the art will recognize thatdifferent cooling systems can be utilized. The combined stream can bepackaged in step 565 or storage, shipping, sale, or consumption. As aresult, the resulting tomato paste product produced with the re-combinedstream has improved color, flavor and viscosity compared to tomato pasteformed by processing unfractionated tomatoes.

[0061] FIGS. 6A-B illustrate an alternative to the method shown in FIGS.5A-B. In FIGS. 6A-B, the initial steps performed in the alternativemethod are the same as the previously describe method. Namely, in steps500-520, tomatoes are chopped, subjected to enzyme removal or breaking,processed using a pulper/finisher, and subjected to preliminaryevaporation, as necessary. The tomato stream is fractionated 525 intoserum and cake portions as previously described. The serum portion isconcentrated in step 530, and the cake portion can be concentrated asnecessary in step 535.

[0062] Instead of re-combining the cake and serum streams as in themethod of FIGS. 5A-B, the serum and cake portions in the alternativeembodiment are individually processed. Specifically, in step 600, theserum portion can be further concentrated if necessary. In steps 605,the serum and cake portions are sterilized as necessary. Thesterilization step may be optional if the concentration is sufficientlyhigh to limit microbiological activity. In this alternative case,refrigerated storage maybe used. In step 610, the serum and cakeportions are cooled. Finally, in step 615, the serum and cake portionscan be individually packaged or further processed. The fractionated cakeand serum portions are packaged for subsequent storage, shipping, sale,or consumption. For example, the tomato portions are transferred to bulkbag in bins, storage tanks or other storage containers. The final serumproduct can have a concentration of about 22-75 brix. The final cakeproduct can have a concentration of about 3-13 brix or can be dehydratedinto a powder with less than 10% moisture.

[0063] The previously described method and system result in a tomatopaste with enhanced attributes compared to tomato paste and tomatoproducts produced by known systems. For example, tomato paste producedwith the present system and method has improved color, flavor, andviscosity. Moreover, the improved tomato paste product is produced in amore cost efficient manner since smaller and less expensive and moreenergy-efficient evaporators can be used to fractionate the tomato juiceinto a more viscous and less viscous portions. As a result, reduced“burn on” occurs in the evaporator. The evaporator can concentrate thethinner serum, whereas a drying mechanism can evaporate or concentratethe cake as necessary, thereby reducing cake burn which would otherwiseoccur when processing unfractionated streams. Moreover, since the serumis significantly thinner than an unfractionated stream, the serum can beconcentrated with the evaporator more quickly than the time required toconcentrate an unfractionated stream. As a result, residence time of theproducts in the evaporator decreases and operating costs are reduced.Thus, the present system and method provide flexibility in selectingsystem portions, is more cost and time efficient, and produces higherquality tomato paste, serum, cake and other products similar or relatedto tomatoes.

[0064] Although references have been made in the foregoing descriptionto various embodiments, persons of ordinary skill in the art of foodpreparation methods and systems will recognize that insubstantialmodifications, alterations, and substitutions can be made to thedescribed embodiments without departing from the invention as claimed inthe accompanying claims. Thus, while the preferred embodiment isdescribed as utilizing tomatoes, those skilled in the art will recognizethat other similar tomato products and fruits and vegetables havingsimilar viscosity characteristics can be processed. Further, persons ofordinary skill in the art will recognize that the example ranges ofconcentrations, temperatures, durations, and vacuum are recited forpurposes of explanation. Indeed, other ranges can be utilized dependingon the system portions and desired product characteristics. Moreover,those persons of ordinary skill in the art will recognize that variousdecanters, evaporators, driers and re-combiners can be used to processfractionated or re-combined cake and serum streams.

1. A method of processing tomatoes to form a tomato product, comprising:separating a tomato stream into a first portion comprising a cakeportion and a second portion comprising a serum portion using a decanterthat includes a weir and a scraping mechanism by rotating said decanterto force said cake portion against an inner surface of said decanter,separating said cake and serum portions with said weir, and removingsaid cake portion collected along said inner surface with said scrapingmechanism, said cake portion having a greater viscosity than said serumportion; concentrating said serum portion; and combining said cakeportion and said concentrated serum portion to yield the tomato product.2. The method of claim 1, wherein separating said tomato stream furthercomprises separating a tomato juice stream formed from raw tomatoes. 3.(Cancelled).
 4. (Cancelled).
 5. The method of claim 1, wherein saidfirst portion comprises about 5% to 35% of said tomato stream by weight.6. The method of claim 1, wherein said first portion comprises about 5%to 60% insoluble solids by weight.
 7. The method of claim 1, whereinsaid cake first portion comprises about 3% to 16% soluble solids byweight.
 8. The method of claim 1, wherein said first portion has aconcentration of about 3 to 13 brix.
 9. The method of claim 1, whereinsaid first portion includes a majority of a color compound relative tosaid second portion.
 10. The method of claim 9, wherein said colorcompound comprises lycopene.
 11. The method of claim 1, wherein saidfirst portion includes a majority of insoluble solids relative to saidsecond portion.
 12. The method of claim 1, wherein said second portioncomprises about 65% to 95% of said tomato stream by weight.
 13. Themethod of claim 1, wherein said second portion comprises about 0.01% to10% insoluble solids by weight.
 14. The method of claim 1, wherein saidsecond portion comprises about 3% to 17% soluble solids by weight. 15.The method of claim 1, wherein said second portion has a concentrationof about 3 to 16 brix.
 16. The method of claim 1, wherein saidconcentrated second portion has a concentration of about 22 to 75 brix.17. The method of claim 1, before separating said stream into said firstand second portions, further comprising processing the tomato productinto said tomato stream.
 18. The method of claim 17, wherein processingthe tomato product further comprises: chopping one or more tomatoes intotomato pieces; and removing solids from said tomato pieces.
 19. Themethod of claim 18, wherein removing said solids further comprisesfiltering tomato skins and seeds with a filter screen.
 20. The method ofclaim 1, further comprising inactivating one or more enzymes in saidstream.
 21. The method of claim 20, wherein said one or more enzymes ispectin galacturonase or pectin methyl esterase.
 22. The method of claim20, wherein inactivating said one or more enzymes further comprisessubjecting said stream to a temperature of about 150 to 230 degreesFahrenheit for a period of about 15 seconds to 10 minutes. 23.(Cancelled).
 24. (Cancelled).
 25. The method of claim 1, furthercomprising removing said first portion collected against said innersurface through a first portion outlet of said decanter.
 26. The methodof claim 1, further comprising removing said second portion within saiddecanter through a second portion outlet of said decanter.
 27. Themethod of claim 1, wherein concentrating said second portion furthercomprises concentrating said stream at a temperature of about 190 toabout 210 degrees Fahrenheit in a vacuum of about 10 to about 30 Hg. 28.The method of claim 1, wherein concentrating said second portion furthercomprises dehydrating said second portion with an evaporator.
 29. Themethod of claim 28, wherein said evaporator is a thin film evaporator, arising film evaporator, a falling film evaporator, a reverse osmosisconcentrator, or a direct osmosis concentrator.
 30. The method of claim1, further comprising concentrating said first portion.
 31. The methodof claim 30, wherein said first portion is concentrated with a drier.32. The method of claim 1, wherein the tomato product comprises tomatopaste.
 33. A system for processing a tomato stream to form a tomatoproduct, comprising: a decanter including a weir and a scrapingmechanism, said decanter configured to receive the tomato stream, andfractionate the stream into a first portion comprising a cake portionand a second portion comprising a serum portion by rotating saiddecanter and separating said cake and serum portions using said weir,and removing said cake portion collected along an interior surface ofsaid decanter, wherein said cake portion has a greater viscosity thansaid serum portion; an evaporator for concentrating said serum portion;and a combination unit for combining said cake portion and saidconcentrated serum portion to form the tomato product.
 34. The system ofclaim 33, wherein the tomato stream comprises a tomato juice streamformed from raw tomatoes.
 35. (Cancelled).
 36. (Cancelled).
 37. Thesystem of claim 33, wherein said first portion comprises about 5% to 35%of the tomato stream.
 38. The system of claim 33, wherein said firstportion comprises about 5% to 60% insoluble solids.
 39. The system ofclaim 33, wherein said first portion comprises about 3% to 16% solublesolids.
 40. The system of claim 33, wherein said first portion has aconcentration of about 3 to 13 brix.
 41. The system of claim 33, whereinsaid first portion includes a majority of a color compound relative tosaid second portion.
 42. The system of claim 41, wherein said colorcompound comprises lycopene.
 43. The system of claim 33, wherein saidfirst portion includes a majority of insoluble solids relative to saidsecond portion.
 44. The system of claim 33, wherein said second portioncomprises about 65% to 95% of the tomato stream by weight.
 45. Thesystem of claim 33, wherein said second portion comprises about 0.01% to10% insoluble solids by weight.
 46. The system of claim 33, wherein saidsecond portion comprises about 3% to 17% soluble solids by weight. 47.The system of claim 33, wherein said second portion has a concentrationof about 3 to 16 brix.
 48. The system of claim 33, wherein saidconcentrated second portion has a concentration of about 22 to 75 brix.49. The system of claim 33, further comprising a processing system forprocessing tomatoes into the tomato stream.
 50. The system of claim 49wherein said processing system comprises a chopper for cutting tomatoesinto tomato pieces; and a pulper for removing solids from said tomatopieces.
 51. The system of claim 50 wherein said pulper is configured toremove solids comprising skins and seeds by filtering said solids with afilter screen.
 52. The system of claim 33, further comprising an enzymedeactivation system for inactivating one or more enzymes in the tomatostream.
 53. The system of claim 52, wherein said one or more enzymes ispectin galacuronase or pectin methyl esterase.
 54. The system of claim52, wherein said enzyme inactivation system is configured to inactivatesaid one or more enzymes by subjecting the stream to a temperature ofabout 150 to 230 degrees Fahrenheit for a period of about 15 seconds to10 minutes.
 55. (Cancelled).
 56. The system of claim 33, wherein saiddecanter defines a first portion outlet through which said first portioncollected against said inner surface of said decanter is removed. 57.The system of claim 33, wherein said decanter defines a second portionoutlet through which said second portion is removed.
 58. The system ofclaim 33, wherein said evaporator concentrates said second portion at atemperature of about 190 to about 210 degrees Fahrenheit in a vacuum ofabout 10 to 30 Hg.
 59. The system of claim 33, wherein said evaporatoris a thin film evaporator, a rising film evaporator, a falling filmevaporator, a reverse osmosis concentrator or a direct osmosisconcentrator.
 60. The system of claim 33, further comprising a drier forconcentrating said first portion.
 61. The system of claim 33, whereinsaid tomato product comprises tomato paste.
 62. (Cancelled). 63.(Cancelled).
 64. (Cancelled).
 65. (Cancelled).
 66. (Cancelled).
 67. Asystem for processing tomatoes to form a tomato paste, comprising: adecanter including a weir and a scraping mechanism, said decanterconfigured to receive said tomatoes and fractionate said tomatoes into acake portion and a serum portion, wherein said cake portion has agreater viscosity than said serum portion by rotating said decanter andseparating said cake and serum portions using said weir, and removingsaid cake portion collected along an interior surface of said decanter,wherein said cake portion has a greater viscosity than said serumportion; an evaporator for concentrating said serum portion; a drier forconcentrating said cake portion; and a combination unit for combiningsaid concentrated cake and concentrated serum portions to form thetomato paste.
 68. (Cancelled).
 69. (Cancelled).
 70. (Cancelled). 71.(Cancelled).